Vitamin B12 and folic acid deficiency causes:

Correct option is B

Ans. (b)
Sol. Megaloblastic anaemia is caused by a deficiency of Vitamin B12 (Cobalamin) and Folic Acid (Vitamin B9), both of which are essential for DNA synthesis and red blood cell (RBC) maturation. A deficiency leads to impaired RBC production, resulting in large, immature, and dysfunctional red blood cells (megaloblasts). This condition can cause fatigue, pallor, shortness of breath, and neurological symptoms (in B12 deficiency).
Explanation of each option:
· (a) Iron deficiency anaemia – Incorrect. This is caused by low iron levels, leading to microcytic, hypochromic RBCs, not megaloblasts.
· (b) Megaloblastic anaemia – Correct. Deficiency of Vitamin B12 and folic acid impairs DNA synthesis, leading to megaloblastic anaemia with large, immature RBCs.
· (c) Sickle cell anaemia – Incorrect. Sickle cell anaemia is a genetic disorder caused by abnormal hemoglobin S, leading to sickle-shaped RBCs.
· (d) Thalassemia – Incorrect. Thalassemia is a hereditary haemoglobinopathy, affecting globin chain production, leading to microcytic anaemia.
Thus, the correct answer is (b) Megaloblastic anaemia, as it results from Vitamin B12 and folic acid deficiency.